1. FIELD OF THE INVENTION
The invention relates to submersible pumps employed in many industrial applications to pressurize fluid containing significant amounts of particulates. Such pumps are often used in the bottom of an oil well wherein the fluid being pumped from the well contains a substantial amount of sand or other particulate matter.
2. DESCRIPTION OF THE PRIOR ART
Submersible pumps heretofore employed in oil wells or other pumping applications involving fluids containing significant quantities of abrasive particulate matter have been plagued with the rapid destruction of the bearing and seal components of the pump by the abrasive action of the particulates contained in the fluid. It is a practical impossibility to effect a complete sealing of each pump bearing and each pump seal from at least exposure at one axial end or the other to the fluid containing the abrasive particulate matter. Accordingly, the prior art has had to resort to the use of exotic materials and expensive bearing and seal constructions in order to minimize the abrasive effects of such particulates.
Such submersible pumps must necessarily be of restricted diameter in order to permit them to be inserted within the oil well casing. Hence, a further problem has been encountered in providing means for neutralizing the thrust reaction force produced by the operation of the pumping stages of the pumping apparatus.